Blisters or Vesicles in Atopic Dermatitis

Atopic dermatitis (AD) causes changes on the visible surface of the skin, as well as the deeper layers of the skin. AD often causes dry, scaly patches of inflammation, and most frequently begins in childhood, although some cases persist or begin in adulthood. In addition to the dry, scaly patches, some people experience blisters or vesicles with AD. (Vesicles are fluid-filled bumps.)¹

How does eczema cause blisters and vesicles?

The body naturally forms blisters when the skin has been damaged by friction, such as rubbing, or due to exposure to heat, cold, or a chemical. atopic dermatitis is caused by a combination of genetic, immunologic, and environmental factors.

Filaggrin mutations damage the skin barrier

In people with atopic dermatitis, there is a decrease or lack of filaggrin in the skin. Filaggrin is a protein that plays a key role in the structure and formation of the corneal layer of the skin. The lack of filaggrin has been traced back to genetic mutations in the FLG gene. Not having enough filaggrin in the skin layers creates a damaged skin barrier, leading to a reduced ability to maintain the skin’s natural amount of water, as well as the sores and rash of AD.

Filaggrin mutations affect the pH of the skin barrier

The damaged skin barrier may also allow for the entry of airborne allergens to enter the skin, which could lead to an inflammatory response by the immune system. Another theory suggests that the normal pH of the skin barrier may be affected by filaggrin defects, which could lead to the overgrowth of bacteria. This could then trigger the immune system to create inflammatory skin lesions.

Immune system dynsfunction and eczema

There is also emerging evidence that the dysfunction in the immune system in patients with eczema not only causes disease but also decreases the amount of functional filaggrin. Immune system dysfunction also creates an increase in inflammation in people with AD.^2,3

Intense itch and repeated scratching

In addition, the intense itch caused by atopic dermatitis leads to repeated scratching and rubbing of the area, which can cause blisters or vesicles to form.

What causes the eczema itch?

The exact disease processes that cause itch in atopic dermatitis are not completely understood, but doctors know that the “itch-scratch cycle” (the skin feels itchy, which leads to scratching, which then causes the skin to feel even more itchy) perpetuates the disease. The itch appears to start before the plaques or inflammation. Research has uncovered that itch in AD is related to the close relationship between the nervous system and the skin. The nerves in the skin send an “itch” message to the brain through chemical messengers called cytokines. Researchers are studying the different mechanisms related to itch, including how people with AD may have skin sensitivity that causes other sensations, such as heat or pain, to be perceived as itch.^4,5

Can infections cause blisters and vesicles?

Blisters can also form in people with atopic dermatitis who have a viral infection, such as an infection of herpes simplex virus (HSV). Due to the dysfunction in the immune system, people with AD are at an increased risk of serious viral infections of the skin. Herpes simplex virus infection is fairly common, and because it is contagious, direct contact with someone who has active cold sores should be avoided. Because of the skin barrier damage in people with AD, these viruses have the potential to spread and may become life-threatening, and prompt medical attention and treatment are required.^6,7

How are they treated?

People with atopic dermatitis are treated with a combination of good skin care, including regular use of moisturizers, and different therapies. Moisturizers are one of the basic necessities for people with AD, regardless of the severity of their disease. Moisturizers help repair the damaged skin barrier caused by AD and help retain needed moisture in the skin.

Medications

Medications used in the treatment of atopic dermatitis include:

• Topical corticosteroids, to reduce redness, inflammation, and itching
• Topical calcineurin inhibitors, to stop the dysfunctional immune response and reduce redness and itching
• Immunosuppressants, which also target the dysfunctional immune response to reduce symptoms
• Antibiotics and antivirals, to fight infection⁸

Wet wrap therapy

Wet-wrap therapy, with or without a topical corticosteroid, is another technique that can help weepy sores from atopic dermatitis. Wet- wrap therapy involves applying the medication (if using) and wrapping the affected area in a layer of wetted gauze, cotton, or bandages, followed by a layer of dry bandages. Wet-wrap therapy helps improve the moisture of the affected skin, improves the penetration of the topical medicine, and provides a physical barrier against scratching.⁸

Other symptoms of atopic dermatitis

In addition to blisters and vesicles, atopic dermatitis can cause a rash, scaly patches, itch, bumps or papules, blisters, and a change in skin color. Some people also experience eye symptoms or cracks behind the ears. Over time, the areas of skin affected by AD may become thickened.